Rack for pressurized gas bottles

ABSTRACT

A rack assembly for transportation of pressurized gas bottles in a vehicle has a first rack on one side and a second rack on the other side each supporting five upright bottles in a row, together with a rigid transverse brace structure connecting between an upper part of the first rack and an upper part of the second rack to hold the first and second rack members in braced position at said first and second sides. Each of the racks is formed by an inner and an outer plate member each having five part circular cut outs in the adjacent surfaces surrounded by a resilient strip for clamping the bottles side by side by an over-center latch which tightens the members together.

BACKGROUND OF THE INVENTION

Pressurized gas bottles are commonly used in many industrial processesand supply many different gases for many different uses. Many of thesegases are hazardous and hence release of the gas can be dangerous and insome cases explosions can occur. Transportation of such bottles whichoften weight of the order of 150 lbs. is common so that they can bemoved to a site of use from a site of production or storage. In theevent of any kind of accident during the transportation, the bottles canbe released from their transport position with the potential forcatastrophic results.

Typically such bottles are transported in upright position often alongthe sides of a transport trailer where the bottom of the bottle isinserted in a wooden rack and the top of the bottle is simply chained tothe side wall. In the event of any impact with the vehicle, the bottlescan readily break free. In the event of a roll over of the vehicle thebottles can be released from their position of storage and free to moveto any location inside or outside the vehicle. Up until now littleattention appears to have been applied to proper restraint of thebottles during transportation.

A number of previous proposals provide brackets which attach to asupport wall such as the side wall of a vehicle and which engage anupper part of the bottles. However these brackets assume structuralintegrity of the support wall which may not be sufficient strong toaccommodate the forces involved in an accident, bearing in mind that arow of such bottles can weight as much as 1000 lbs.

One example of an arrangement of this type is shown in U.S. Pat. No.3,643,813 (Noonan) issued Feb. 22, 1972 where a number of such bottlesare attached to a rail in two or more rows. However the structuralintegrity of the rail itself is not addressed.

A number of other alternatives provide a frame or container in the formof a palette which can be independently moved from place to placecarrying a series of the bottles. One example is shown in U.S. Pat. No.4,564,109 (Stavio) issued Jan. 14, 1986 which discloses a containerplaced upon a palette for containing two rows of such bottles with anupstanding and overlying rail by which the palettes can be lifted.

However none of these arrangements are suitable to provide an effectivemounting of the bottles during transportation in a manner which canmaintain the bottles properly retained in place even in the event of aserious accident.

SUMMARY OF THE INVENTION

It is one object of the invention to provide an improved rack which moreeffectively supports gas bottles during transportation in atransportation vehicle to reduce the potential for dangerous materialsto be released after an accident including the vehicle.

According to one aspect of the invention there is provided a rack fortransportation of pressurized gas bottles in a transportation vehiclecomprising:

a first rack member for engaging and supporting a first plurality of thebottles in upstanding orientation;

the first rack member having an upper bottle engagement member forrigidly engaging an upper part of each of the bottles;

the first rack member having a lower bottle engagement member forrigidly engaging a lower part of each of the bottles;

the first rack member having frame members interconnecting the upper andlower bottle engagement members such that the first rack member forms arigid structure for upstanding along a first side of the transportationvehicle and for holding the bottles in rigid upright position along saidfirst side;

a second rack member for engaging and supporting a second plurality ofthe bottles in upstanding orientation;

the second rack member having an upper bottle engagement member forrigidly engaging an upper part of each of the bottles;

the second rack member having a lower bottle engagement member forrigidly engaging a lower part of each of the bottles;

the second rack member having frame members interconnecting the upperand lower bottle engagement members such that the second rack memberforms a rigid structure for upstanding along a second side of thetransportation vehicle and for holding the bottles in rigid uprightposition along said second side;

and a rigid transverse brace structure for connecting between an upperpart of the first rack member and an upper part of the second rackmember to hold the first and second rack members in fixed bracedposition at said first and second sides.

Preferably each of the first and second rack members is arranged tosupport the plurality of bottles in a single row.

Preferably each of the bottle engagement members forms a clamp forclamping around the plurality of bottles.

Preferably the clamp has two rigid members each having a plurality ofrecesses each for partly surrounding a respective one of the bottles anda tensioning element for drawing the two rigid members together

Preferably the tensioning element is an over-center latch.

Preferably the over-center latch is adjustable to adjust tension betweenthe rigid members

Preferably each of the two rigid members of the clamp are cut fromplate.

Preferably each of the two rigid members of the clamp are formed by atop plate and turned down sides welded to form a box structure

Preferably each of the recesses is defined by an edge of a plate and hasa resilient strip around the edge for resiliently engaging an outersurface of the respective bottle.

Preferably the lower bottle engagement member has an outer rigid memberfixed to the frame members and an inner rigid member movable relative tothe frame members with the outer rigid member having a flat base forreceiving a bottom apex of the bottles when engaged in the upper andlower bottle engagement members.

Preferably the lower bottle engagement member has a flat base forreceiving a bottom apex of the bottles when engaged in the upper andlower bottle engagement members and wherein the flat base is covered bya resilient material.

Preferably the upper bottle engagement member has an outer rigid memberfixed to the frame members and an inner rigid member movable relative tothe frame members and wherein the outer rigid member has a supportelement thereon for engaging and supporting the inner rigid member as itmoves in a sliding action relative to the frame members.

Preferably the frame members comprise a row of at least two verticalposts at spaced positions along the side.

Preferably the vertical posts pass through holes in the upper and lowerengagement members.

Preferably the brace structure comprises a plurality of rails eachextending across from one of the posts of the first rack member to acorresponding post of the second rack member.

According to a second aspect of the invention there is provided atransportation vehicle for transportation of pressurized gas bottles ina comprising:

a vehicle box having a floor, a roof and a first and a second side wall;

a first rack member for engaging and supporting a first plurality of thebottles in upstanding orientation;

the first rack member having an upper bottle engagement member forrigidly engaging an upper part of each of the bottles;

the first rack member having a lower bottle engagement member forrigidly engaging a lower part of each of the bottles;

the first rack member having frame members interconnecting the upper andlower bottle engagement members such that the first rack member forms arigid structure for holding the bottles in rigid upright position;

the first rack member being arranged in upstanding position along thefirst side of the transportation vehicle;

the first rack member being fastened to the floor of the transportationvehicle;

a second rack member for engaging and supporting a second plurality ofthe bottles in upstanding orientation;

the second rack member having an upper bottle engagement member forrigidly engaging an upper part of each of the bottles;

the second rack member having a lower bottle engagement member forrigidly engaging a lower part of each of the bottles;

the second rack member having frame members interconnecting the upperand lower bottle engagement members such that the second rack memberforms a rigid structure for holding the bottles in rigid uprightposition;

the second rack member being arranged in upstanding position along thesecond side of the transportation vehicle;

the second rack member being fastened to the floor of the transportationvehicle;

and a rigid transverse brace structure extending across the roof andconnecting an upper part of the first rack member and an upper part ofthe second rack member to hold the first and second rack members infixed braced position at said first and second sides.

According to a third aspect of the invention there is provided a rackfor transportation of pressurized gas bottles in a transportationvehicle comprising:

a rack member for engaging and supporting a first plurality of thebottles in a row in upstanding orientation;

the rack member having an upper bottle engagement member for rigidlyengaging an upper part of each of the bottles;

the rack member having a lower bottle engagement member for rigidlyengaging a lower part of each of the bottles;

the rack member having frame members interconnecting the upper and lowerbottle engagement members such that the rack member forms a rigidstructure for holding the bottles in rigid upright orientation;

wherein each of the bottle engagement members forms a clamp for clampingaround the plurality of bottles with the clamp having a first rigidmember having a plurality of recesses each for partly surrounding arespective one of the bottles and a second rigid member having aplurality of recesses each for partly surrounding a respective one ofthe bottles facing the first rigid member, and a tensioning element fordrawing the two rigid members together.

BRIEF DESCRIPTION OF THE DRAWINGS

One embodiment of the invention will now be described in conjunctionwith the accompanying drawings in which:

FIG. 1 is a rear elevational view of a rack according to the presentinvention mounted in a vehicle with the rear of the vehicle open toexpose the structure of the rack.

FIG. 2 is a view along the lines 2-2 of FIG. 1 showing the rackseparated from the vehicle.

FIG. 3 is a cross sectional view along the lines 3-3 of FIG. 2 butshowing the lower one of the two bottle engaging members.

FIG. 4 is an end elevational view of the upper bottle engaging member ofFIG. 2.

FIG. 5 is a top plan view of the rack in place in the vehicle of FIG. 1.

In the drawings like characters of reference indicate correspondingparts in the different figures.

DETAILED DESCRIPTION

In FIG. 1 and also shown in FIG. 5 is shown a vehicle 10 which in mostcases form a trailer for attachment to a towing vehicle but may beitself a self-propelled vehicle such as a truck. The vehicle includes arear box having a floor 11, a roof 12 and side walls 13 and 14. Thestructure of these is shown only schematically since the structure ofsuch vehicles can vary and is well known to a person skilled in the art.In most cases the vehicle will have posts and rails forming a structurefor the walls and floor to provide some structural integrity and loadbearing capability. However the present arrangement can be used withvehicles of different types having different arrangements for thestructural integrity since the device is intended to provide its ownstructural strength.

The apparatus thus comprises a first rack member 15 containing a seriesof bottles 16 in a row along the side wall 14. The apparatus furthercomprises a second rack member 17 containing bottles 16 again arrangedin a row along the side wall 13. The racks 15 and 17 are substantiallyidentical but of course reversed so as to face inwardly. Each of therack members comprises an upper bottle engaging member 19, a lowerbottle engaging member 20 and frame members 21 thus providing anupstanding substantially rigid structure for standing along therespective side wall. In addition the rack member can include a rail 22arranged to extend between the frame members 21 at a heightapproximately equal to or just above the top of the bottle with theframe member having a series of pins standing upwardly and locatedbetween each bottle and the next so that a chain 23 can be used as atemporary safety measure to hold the bottles upright when the bottleengaging members are released. The chain of course is not intended toact as a restraint except as a temporary safety measure. Thus the chainmay be simply dropped over upstanding pins on the rail 22 to loop aroundthe upper valve section of the bottle.

The frame members 21 comprise two or more upstanding posts. In theembodiment shown there are two such posts arranged at opposite ends ofthe rack member and standing upwardly along the side wall to an upperend 24 of the posts. At the upper end, each post is connected to atransverse rail 25 by an angle bracket 26 so that the transverse rail 25extends across the roof 12 and connects between the posts of one rackmember and the corresponding post of the opposite rack member. Thusthere are an equal number of rails 25 to the number of posts 21 thusforming a rigid rectangular structure defined by the upstanding rackmembers and the transverse rails.

The bottom bottle engaging members are attached rigidly to the floor 11by suitable bolts which extend through the floor and into a suitablestructural member or through the floor as lag bolts. The posts may beconnected to the wall for increased structural stability. However thetransverse rails 25 provide a connection between the top of the rackmembers which can accommodate impact damage on the vehicle and even rollover of the vehicle since the rack members and the transverse rails formin effect a structural cage in the interior of the vehicle.

Turning now to FIGS. 2, 3 and 4, there is shown more detail of thestructure of the rack members. Thus the rack member includes the upperand lower bottle engaging members 19 and 20 and these are basically ofthe same structure which is of the construction shown in FIGS. 2, 3 and4. The differences between the two bottle engaging members will bedescribed in more detail hereinafter. Thus each of the bottle engagingmembers comprises an outer clamping element 30 and an inner clampingelement 31. Each of these is formed by sheet metal which is bent to forma top plate 32 and a depending side wall 33. Thus the inner clampingmember 31 has the top wall 32 and the depending side wall 33 and alsodepending end walls 34 and 35. These are welded at the corners 36 and 37to form in effect a box structure with an open bottom. The side wallsprovide increased structural strength for the top plate 32 to preventbending of that top plate. Symmetrically the outer clamping element 30includes a top wall or plate 38, a side wall 39 and end walls 40. Eachof the top plates 32 and 38 is cut to form a series of part circularrecesses 41 and 42 respectively. In the embodiment shown there are fivesuch recesses for receiving five bottles. It will be appreciated thatthe number of bottles can be increased or decreased as required andtypical examples of such racks may include only two bottles. In theevent that more than five bottles along each side are intended to bestored, it is common that a second rack of the five bottle constructionwill be utilized rather than manufacture a rack of an increaseddimension.

Along the recesses at the cut edge of the metal plate is provided aresilient strip 43 which is of a commercially available constructionincluding a tubular bead 44 and a clamping slot 45 which engages ontothe edge 46 of the metal plate. The clamping slot 45 clips onto the edgeand is commonly retained by friction but the retaining forces may beincreased by adhesive if required. The bead 44 is resilient andcompressible so that the bead provides a clamping force onto the bottlebut spreads that clamping force around the periphery of the bead toavoid metal to metal contact and to allow increased force to be appliedwithout locating that force at specific points of contact.

The bead 43 extends along the full length of the cut edge of theclamping member from one end wall 34 to the other end wall 35. The endwall 34 of the outer clamping member has an end edge 34A which is spacedaway from an end edge 40A of the end wall 40 of the inner clampingmember. These end edges are pulled together in a clamping action by anover-center toggle latch generally indicated at 46. The toggle latch 46includes a bracket 47 attached to the end wall 40 which has hook section48 at the end adjacent the outer clamping member which engages with aloop 49 attached to the end wall 34 of the outer clamping member. Thisloop 49 is carried on a pin 50 and is adjustable relative thereto in adirection along the end wall 34 by a screw section 51. The pin 50 iscarried on a lever 52 pivotally mounted on a bracket 53 so that a handleend 54 of the lever can be grasped and pivoted away from the end wall 34on the vertical axis defined by the bracket 53 so as to move the pin 50away from the end wall and toward the outer clamping member so as torelease the loop 49 from the hook 48. Such over-center toggle latchesare of course well known and commercially available but provide aneffective way of tensioning the outer clamp member against the innerclamp member thus pulling the beads 43 against the peripheral wall ofthe bottle.

The bottom bottle engaging member 20 sits on the floor and is clamped tothe floor. Thus the bottom bottle engaging member is shown in FIG. 3 andincludes a base plate 60 which is attached to the side wall 39 andprojects therefrom horizontally across the floor to an outer edge 61beneath the underside of the inner clamping member 31. This base plate60 can be fastened to the floor by suitable fasteners 63 which can bescrews as shown or can be lag bolts or other elements connected tostructural members of the floor as required and as suitable dependingupon the structure of the vehicle. The base plate 60 carries a resilientlayer of a fibrous material as indicated at 64 for engaging the apex 65of the domed section 66 of the bottom of the bottle 16. The height ofthe walls 33 and 39 are arranged so that the bead 43 is located on thebottle at a position just beyond the end of the domed section 66 andinto the cylindrical section of the bottle so as to clamp against thatcylindrical section and to provide a grasping action on the cylindricalsection. The height therefore can be of the order of three inches whichis typical for bottles of this type.

The inner clamping element 31 of the bottom bottle engaging member 20can sit on the floor when not in use so that its bottom edges of itsside and end walls rest on the floor. They can then simply slide acrossthe floor to the engagement position shown in FIG. 3.

The upper bottle engaging member which is shown in FIG. 4 and indicatedat 19 is slightly modified in that there is no base plate 60 since theupper bottle engagement member engages the bottle at a position part wayalong its height. In addition it is necessary to support the innerclamping member 31 when it is released from clamping action and tolocate it when it is required to slide into the clamping position. Thusthe outer clamping member 30 includes a support rail 65 which projectsbeyond the end wall 40A there is a horizontal support surface 66 forengaging the bottom edge of the end walls 34 of the inner clampingmember 31. A guide slot 67 can be provided mounted either on the bottomedge of the wall 34 or on the top edge of the rail 65 to hold the innerclamping member 31 in place when it is released from the latch 46.

The top wall of the outer clamping member 30 is cut to define openingsfor the posts 21. Each of the posts 21 is in the form of a channel withan outwardly facing base 21A and two inwardly extending legs 21B and21C. The upper wall of the outer clamping member 30 is thus cut to forma slot to which the channel-shaped post 21 can be inserted. The post 21is then bolted to the end wall 40 of the outer clamping member by bolts68. In the upper member 19, these bolts 68 are spaced by the height ofthe outer clamping member 30 which includes the rail section 65. Thisprovides additional structural strength. At the bottom as shown in FIG.3, the bolts 68 are located within the three inch height of the outerclamping member on the end wall 40 thereof. As these bolts are hiddeninside the frame structure of the rack member, this prevents a potentialthief from accessing the bolts when the structure is in place and thebottles are loaded so that easy opening of the structure and release ofthe bottles is inhibited. For this purpose also the toggle latchincludes a flange 70 which allows a lock to be inserted to hold thelatch in the closed position. In this way security is increased andtheft is inhibited.

And the fact that the rails pass through the structure of the outerclamping members increases structural strength and prevents the outerclamping members from being released from the posts in the event ofsignificant impact which cause bending or distortion of the posts.However even in such a circumstance the outer clamping member remainsattached onto the posts holding the bottles in place.

The horizontal rails 25 which connect the posts 21 are also formed aschannel members providing significant structural strength. They can beformed as angles or tubes. The angle bracket 26 is in the form of a flatplate with two legs at right angles where each plate is bolted to thebase of the channel of the post at one side and the rail at the otherside. This again provides a structural connection between the rails andthe posts which ensures that the structure remains integral even ifdistorted in an impact or roll over.

Thus the structure holds the bottles rigidly and permanently attached tothe rack by the use of the inner and outer clamping members which areintegrally formed by elements which surround all of the bottles of therow. Thus the outer clamping member engages one half of each of thebottles of the row and holds those bottles to the rails. The innerclamping member is clamped to the outer clamping member by the togglelatch and itself is an integral structure engaging each of the bottlesthus holding the bottles side by side and ensuring that they are firmlyheld between the two clamping members. The bottles cannot lift as theyare clamped vigorously by the clamping action of the beads. In this waythe potential for release of hazardous materials for the escape of apotentially explosive bottle is significantly reduced.

Since various modifications can be made in my invention as herein abovedescribed, and many apparently widely different embodiments of same madewithin the spirit and scope of the claims without department from suchspirit and scope, it is intended that all matter contained in theaccompanying specification shall be interpreted as illustrative only andnot in a limiting sense.

1. A rack for transportation of pressurized gas bottles in atransportation vehicle comprising: a first rack member for engaging andsupporting a first plurality of the bottles in upstanding orientation;the first rack member having an upper bottle engagement member forrigidly engaging an upper part of each of the bottles; the first rackmember having a lower bottle engagement member for rigidly engaging alower part of each of the bottles; the first rack member having framemembers interconnecting the upper and lower bottle engagement memberssuch that the first rack member forms a rigid structure for upstandingalong a first side of the transportation vehicle and for holding thebottles in rigid upright position along said first side; a second rackmember for engaging and supporting a second plurality of the bottles inupstanding orientation; the second rack member having an upper bottleengagement member for rigidly engaging an upper part of each of thebottles; the second rack member having a lower bottle engagement memberfor rigidly engaging a lower part of each of the bottles; the secondrack member having frame members interconnecting the upper and lowerbottle engagement members such that the second rack member forms a rigidstructure for upstanding along a second side of the transportationvehicle and for holding the bottles in rigid upright position along saidsecond side; and a rigid transverse brace structure for connectingbetween an upper part of the first rack member and an upper part of thesecond rack member to hold the first and second rack members in fixedbraced position at said first and second sides.
 2. The rack according toclaim 1 wherein each of the first and second rack members is arranged tosupport the plurality of bottles in a single row.
 3. The rack accordingto claim 2 wherein each of the bottle engagement members forms a clampfor clamping around the plurality of bottles.
 4. The rack according toclaim 3 wherein the clamp has two rigid members each having a pluralityof recesses each for partly surrounding a respective one of the bottlesand a tensioning element for drawing the two rigid members together 5.The rack according to claim 4 wherein the tensioning element is anover-center latch.
 6. The rack according to claim 5 wherein theover-center latch is adjustable to adjust tension between the rigidmembers
 7. The rack according to claim 4 wherein each of the two rigidmembers of the clamp are cut from plate.
 8. The rack according to claim4 wherein each of the two rigid members of the clamp are formed by a topplate and turned down sides welded to form a box structure
 9. The rackaccording to claim 4 wherein each of the recesses is defined by an edgeof a plate and has a resilient strip around the edge for resilientlyengaging an outer surface of the respective bottle.
 10. The rackaccording to claim 1 wherein the lower bottle engagement member has anouter rigid member fixed to the frame members and an inner rigid membermovable relative to the frame members with the outer rigid member havinga flat base for receiving a bottom apex of the bottles when engaged inthe upper and lower bottle engagement members.
 11. The rack according toclaim 1 wherein the lower bottle engagement member has a flat base forreceiving a bottom apex of the bottles when engaged in the upper andlower bottle engagement members and wherein the flat base is covered bya resilient material.
 12. The rack according to claim 1 wherein theupper bottle engagement member has an outer rigid member fixed to theframe members and an inner rigid member movable relative to the framemembers and wherein the outer rigid member has a support element thereonfor engaging and supporting the inner rigid member as it moves in asliding action relative to the frame members.
 13. The rack according toclaim 1 wherein the frame members comprise a row of at least twovertical posts at spaced positions along the side.
 14. The rackaccording to claim 13 wherein the vertical posts pass through holes inthe upper and lower engagement members.
 15. The rack according to claim13 wherein the brace structure comprises a plurality of rails eachextending across from one of the posts of the first rack member to acorresponding post of the second rack member.
 16. A transportationvehicle for transportation of pressurized gas bottles in a comprising: avehicle box having a floor, a roof and a first and a second side wall; afirst rack member for engaging and supporting a first plurality of thebottles in upstanding orientation; the first rack member having an upperbottle engagement member for rigidly engaging an upper part of each ofthe bottles; the first rack member having a lower bottle engagementmember for rigidly engaging a lower part of each of the bottles; thefirst rack member having frame members interconnecting the upper andlower bottle engagement members such that the first rack member forms arigid structure for holding the bottles in rigid upright position; thefirst rack member being arranged in upstanding position along the firstside of the transportation vehicle; the first rack member being fastenedto the floor of the transportation vehicle; a second rack member forengaging and supporting a second plurality of the bottles in upstandingorientation; the second rack member having an upper bottle engagementmember for rigidly engaging an upper part of each of the bottles; thesecond rack member having a lower bottle engagement member for rigidlyengaging a lower part of each of the bottles; the second rack memberhaving frame members interconnecting the upper and lower bottleengagement members such that the second rack member forms a rigidstructure for holding the bottles in rigid upright position; the secondrack member being arranged in upstanding position along the second sideof the transportation vehicle; the second rack member being fastened tothe floor of the transportation vehicle; and a rigid transverse bracestructure extending across the roof and connecting an upper part of thefirst rack member and an upper part of the second rack member to holdthe first and second rack members in fixed braced position at said firstand second sides.
 17. A rack for transportation of pressurized gasbottles in a transportation vehicle comprising: a rack member forengaging and supporting a first plurality of the bottles in a row inupstanding orientation; the rack member having an upper bottleengagement member for rigidly engaging an upper part of each of thebottles; the rack member having a lower bottle engagement member forrigidly engaging a lower part of each of the bottles; the rack memberhaving frame members interconnecting the upper and lower bottleengagement members such that the rack member forms a rigid structure forholding the bottles in rigid upright orientation; wherein each of thebottle engagement members forms a clamp for clamping around theplurality of bottles with the clamp having a first rigid member having aplurality of recesses each for partly surrounding a respective one ofthe bottles and a second rigid member having a plurality of recesseseach for partly surrounding a respective one of the bottles facing thefirst rigid member, and a tensioning element for drawing the two rigidmembers together.
 18. The rack according to claim 17 wherein each of thetwo rigid members of the clamp are formed by a top plate and turned downsides welded to form a box structure
 19. The rack according to claim 17wherein each of the recesses is defined by an edge of a plate and has aresilient strip around the edge for resiliently engaging an outersurface of the respective bottle.
 20. The rack according to claim 17wherein the first rigid member is fixed to the frame members and thesecond rigid member is movable relative to the frame members with thefirst rigid member having a flat base for receiving a bottom apex of thebottles when engaged in the upper and lower bottle engagement members.21. The rack according to claim 17 wherein the lower bottle engagementmember has a flat base for receiving a bottom apex of the bottles whenengaged in the upper and lower bottle engagement members and wherein theflat base is covered by a resilient material.
 22. The rack according toclaim 17 wherein the upper bottle engagement member has the first rigidmember fixed to the frame members and the second rigid member movablerelative to the frame members and wherein the first rigid member has asupport element thereon for engaging and supporting the second rigidmember as it moves in a sliding action relative to the frame members.23. The rack according to claim 17 wherein the frame members comprise arow of at least two vertical posts at spaced positions along the rackmember where the vertical posts pass through holes in the upper andlower engagement members.